Summary: | 碩士 === 國立中正大學 === 機械工程系研究所 === 106 === A cost-effective sensor-embedded smart linear guideway type (LGT) recirculating linear ball bearing, or simply called carriage hereafter, is proposed. Two kinds of sensors are installed on this smart carriage. The first one is an optical mouse sensor which provides the positioning information. The second one is a tactile load cell, called film type pressure sensor, also known as Force Sensitive Resistor (FSR), which measures the forces from the guideway. These two sensors are utilized to monitor the position of the carriage on the linear guideway and the loading change caused by the deformation of linear guideway. By tracking the force variation sensed by the FSR along the guide way, the linear guideway straightness and parallelism between the two linear guideways can be determined indirectly. Results show that the differences in measuring the straightness of reference guideway between the proposed this smart carriage system and dial gauge are less than 50Nt and 4μm, respectively. Results also show that the correlation coefficients in measuring the parallelism of the two linear guideways are more than 0.5. Moreover, the force acting on the screw nut as well as the supported bearing at two ends can be determined when the worktable is traveling, which enables us to calculate the remaining useful life (RUL) of nut and bearings. A ball screw feed drive system with adjustable linear guideways was built to assess the performance of the proposed smart carriage both in its positioning accuracy and the on-line measurement of linear guideway straightness and parallelism as compared to those measured by the optical ruler and dial gauge, respectively.
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